Fluid control systems for powered panels



United States Patent a corporation of Connecticut [54] FLUID CONTROL SYSTEMS FOR POWERED [72] inventor HaroldW.Ferguson 3,183,790 5/1965 Raymond 9l/35(X) New Hartford,Connecticut 3,420,265 1/1969 DePauw 9l/446(X) 21 AppLNo. 750,633 3,439,581 4/1969 Wilkins 91/41o x [22] Filed Aug-6,1968 3,440,932 4/1969 Gutmkovetal. 9l/38(UX) Patmed 3993,1970 Primary Examiner-Everette A. Powell, Jr. Asslgllee Q" $3513! 2 Attorney- Prutyman. Hayes, Kalb & Chilton pressure level. The high-pressure fluid from the source also actson the automatic pressure responsive valve through an adjustable orifice to discontinue the delivery of high-pressure fluid to the piston. The automatic pressure responsive valve is reset gradually through the adjustable orifice after the traffic passes and is ready to initiate a new opening cycle without completion of a prior closing cycle.

LINE PRESSURE PA ENIEnnEcamm 3.545337 I SHEET 1 OF 2 FNVENTOR. HAROLD W. FERGUSON ATTORNEYS FIG. 2

Y LINE PRESSURE TO PISTON 1 FLUID CONTROL SYSTEMS non POWERED PANELS SUMMARY or THE INVENTION This invention pertains generally to control systems for powered panel members such as sliding doors and the like. More particularly, it is concerned with a system-that controls both the sequence and rate of flow of high and low-pressure fluid utilized to move such a panel member.

The fluid-powered mechanisms used for moving panels such as doors generallymust impart high initial force to each door fluid control system for power operators of panel members.

Another object of this invention is to provide a powered panel member with a fluid control systemthat automatically causes a high initial breakaway force to be exerted against the panel member for an adjustable interval, and then causes a force of reduced and controlled magnitude. to be exerted .thereagainst, ensuring completion of movement of the panel memberwith minimum need for against deceleration. v

Another object of the present inventionis to provide a powered panel member with afluid control system utilizing provision of cushioning high-pressure fluid flow tofirst impart breakaway acceleration I to the member attest, foran adjustable interval, to thereafter gradually cut off the said flow and shift 'to fluid flo w of reduced and uniform magnitude, providing transit of the member with reduced momentum, which system is more compact and requires less space than do heretofore utilized boosters and accumulators.

Another object of the invention is to provide a'powered panel member with a fluid control system which is efiective not only in controlling both the sequence and rate of fluid flow used for fully opening a door but is capable also of initiating a new cycle of operation without having completed a full prior cycleofoperatlon. r I

Other objects will be in part obvious and in part pointed out more in detail hereinafter. l i The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified inthe construction hereafter set forth and the scope of the applicationwhich will be indicated in the appended claims.

In the'drawings:

FIG. 1 is a front elevation view, partly broken away, partly in section, and partly schematic, of the control system of the invention, shown operatively associated with a powered panel member;

FIG. 2 is anenlarged front section view, partly broken away and partly schematic, of the control system of FIG. I; and

FIG. 3 is a section view taken substantially along line 3-3 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT ble opening, by means of a pair of door supporting trolleys 14 which can roll along an overhead supporting track 16 concealed within thewall 12. One of the trolleys 14 is provided cycling of the operator. In the embodiment illustrated. a

spring 24 bears against a bidirectional piston 26 which is reciprocably positioned within a cylinder 28 of the operator 22 and normally holds the door closed as in FIG. 1. Fluid such as air under a predetermined line pressure'passes to the pressure responsive control mechanism but is prevented from bearing against the piston 26. A switch responsive solenoid valve 70, shown by full lines inits closed condition in FIG. 2, connects the mechanism 50 with the operator 22 and therefore controls the flow of fluid to the piston 26. The line pressure fluid communicates with a pressure reducing valve 76 adjacent the mechanism 50, as shown, through a main conduit 64 in that mechanism. This conduit also communicates with a conduit 66 of the mechanism, and both a pressure responsive valve 52 reciprocably disposed in a valve chamber 73 which also communicates with the conduit 66, and a needle valve 68 adjustable disposed in the conduit 66. There is fluid communication between the valve 68 and a conduit 74 which communicates with the closed inlet port 70A of the switch responsive valve 70. Fluid communication also is provided past the needle valve 68 to a branch of the conduit 74 that includes a flow valve 86 therein, and a ball 77 of a unidirectional check valve 78 for cutting off communication with conduit 80.

fluid in conduit 74. The pressure responsive valve 52 is normally biased open to its full line fluid pressure passing condition by means of an adjustable spring; 62.,Line 'presstrre fluid reaching conduit 74 from valve 52 is prevented from bearing against piston 26 by means of the closed port 70A of :the switch responsive valve 70. In addition, output port 708 of the valve 70 is closed to the port 70A but communicates with 'exhaust valve port 70C of the said valve, so the fluid pressure in conduit 90 and on the fluid side of the piston 26 equals that at the exhaust port. Similarly, conduit 88 provides an exhaust route to port 70C via port 783 by which valve chamber 73 controlling the valve52 is purged of enough fluid to equalize the pressure therein with that at the exhaust port.

Actuation of either of mat switches 71 shifts the system 30 into its operating mode, by bringing thevalve ports A and 70B into communication with each other and closing the valve port 70C, as shown by dash lines. Line pressure fluid then flows from the main conduit 64 into the conduit 66, through the annulus 54 of the pressure responsive valve. 52 and past the needle valve 68 in the conduit 66 into. the conduit 74. From conduit 74 the fluid flows to and through the now open switch responsive valve 70 and on to bear against the fluid side of the piston 26 via the conduit 90, thus overcoming the bias of the closure spring 24, and the inertia of the door 10, and imparting initial high acceleration thereto, driving it toward the opened position. The needle valve 68 can be utilized to adjust the fluid flow to the piston, and thus the rate of acceleration of the door.

During the foregoing acceleration phase of the systems operating mode, line pressure fluid also flows from the valve 70 through the conduit 88, past an adjustable metering valve 84 and into the valve chamber 73. The time required for fluid to enter the chamber 73 and shift the valve 52 to close conduit 66 can be adjusted with the valve 84, and represents the interval during which the door 10 is accelerated under full line pressure. During this phase of operation, the full line pressure in conduit 74 maintains the check valve 78 closed against the with operator-connecting linkage 18 secured to a piston rod 20, of an operator 22 for ensuring movement of the door between the opened and the closed positions in response to reduced pressure fluid in the conduit 80.

As line pressure fluid enters chamber 73, pressure increases therein and this pressure overcomes the bias of the valve spring 62 which normally holds the valve 52 open moving the valve 52 away from a stop pin 60 fixed. across the chamber 73 against the bias of the spring 62. This movement shifts the an nulus S4 of the valve 52 out of registry with the conduit 66 and so cuts off all flow of line pressure fluid through conduit 66 to switch responsive valve 70 andpower cylinder 28. This flow v.cutoff occurs relatively gradually due to the restriction of l valve 84 and may be adjusted in order to regulate the portion of the cycle during which full line pressure is delivered to cylinder 28.

The cutoff of full line pressure fluid flowing to the switch responsive valve 70 and thence to the piston 26 sufficiently relieves the force of fluid normally seating check valve ball 77 so that fluid from the pressure reducing valve 76 now unseats ball 77. The reduced pressure fluid flows through the conduit 74, across the reduced pressure flow metering valve 86, on to the switch responsive valve 70 and therethrough to the conduit 90, and against the piston 26 with sufficient force to drive the piston and the door at a reduced but uniform rate to its fully opened position. The metering valve 86 can be utilized to adjust the transit velocity of the piston and the door during this phase of operation. Simultaneously with the flow of reduced pressure fluid through the switch responsive valve 70 to the piston 26 reduced pressure fluid flows through the valve 70 into the conduit 88 and past metering valve 84 into chamber 73 imparts enough force to the face 58 of valve 52 to hold the valve closed against the bias of the spring 62. In this low velocity door transit phase of the systems operating mode, the door 10 is driven to its fully opened position at a rate of transit which provides substantially reduced, controlled momentum of the door to minimize the impact forces when the door reaches its open position. Accordingly, any need to cushion the impact is greatly minimized, and in the embodiment shown, the potential energy of the compressed closurespring 24 accommodates what very slight impact may exist.

The door 10 having been opened by the piston 26 under I control of the system 30 will remain open so long as the ports 70A and 70B of the switch responsive valve 70 are in communication. In the disclosed embodiment, so long as there is pressure on either of the mat switches 71, the valve 70 is held in the open condition just described so that fluid flows therethrough to both the piston 26 and the valve chamber 73.

After pressure upon the mat switches 71 has been released, the switch responsive valve 70 will revert to its closed condition as illustrated in the solid lines of FIG. 2. As a result, the fluid pressure to the piston 26 is cut off and the exhaust routes from the piston and from the valve chamber 73 are opened. The force of closure spring 24 now urges the piston 26 and the door 10 in the reverse direction, driving fluid in cylinder 28 back through the conduit 90, past the port 708 and out through the exhaust port 70C. Simultaneously, the spring 62 urges the valve 52 toward the right (as viewed in FIG. 2) by exhausting the chamber 73 past the metering valve 84, conduit 88 and switch responsive valve 70, thus gradually bringing the annulus 54 into registry with the conduit 66. Until the valve 52 engages stop pin 60 and the annulus 54 fully registers with conduit 66, valve 52 acts as a progressively less effective flow metering device, and a recycle beginning during this phase of operation by the closing of mat switch 71 will result in the delivery of fluid to power. cylinder 28 at a pressure somewhai less than full line pressure depending upon the flow restriction offered by valve 52. In this way, high impact forces at stroke limit are avoided upon short recycles.

Precise control of the forces needed to shift the valve 52 during operation of the system 30 is obtained with appropriate adjustments of the bias of the spring 62 and the flow restriction offered by the valve 84. When proper adjustments of these elements have been effected, the valve 52 will reliably and gradually shift as the required pressure is built up in the cavity 72, and then again as that pressure is reduced during exhausting.

The novel fluid control system of the invention thus provides an adjustable initial high acceleration of a panel member such as a door movable relatively to a fixed structure, and an automatically controlled completion of mo\ ement of the door in the same direction at a reduced and unform rate, greatly minimizing need to cushion the door against deceleration impact. That is, the door is moved by a strong first force and then continuously and smoothly by a second and lesser, steady force, as opposed to being moved by one force which is partly checked as the door is stopped. The inventive system is also more compact than the booster cylinder and accumulatortype mechanisms, and thus readily tits in confined header installations. The system is disclosedin a sliding door environment, but is adaptable to other types of installation, such as are used for swinging doors. With appropriate "sensing'and switching means, the system safely and surely accommodates itself automatically throughout a door transit cycle upon sensing abnormal conditions such as a pedestrian blocking the door transit path.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readilyapparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims. For example, the system can be adapted to function by liquid power orby gas power, and can also be adapted to function bidirectionally, whereby the panel member would be driven in both directions by fluid means and the closure spring would be eliminated.

lclaim:

1. in a fluid-powered panel regulating and operating system having a fluid operator responsive to demand signals, the improvement including an'inertia-overcoming accelerator for imparting an initial, breakaway driving force to the panel upon receipt of a demand signal, said initial force-being of short duration relative tothe complete movement of the panel in the same direction, said accelerator comprising a self-closing line carrying pressurized driving fluid to the operator for imparting the breakaway driving force to the panel, a fluid control valve in the self-closing line movable to a closed position by pressurized driving fluid that has passed through the valve during breakaway movement of the panel, a line carrying fluid under reduced pressure to the operator for automatically completing the movement of the panel after the closing of the valve.

2. The system claimed in claim 1 including an adjustable control for the self-closing valve for regulating the duration of said initial force.

3. The system claimed in claim 2 wherein the adjustable control includes means associated with the valve for receiving fluid under pressure, to close the valve.

4. The system claimed in claim 1 in which means are provided to bias the fluid control valve to its opened and pressurized fluid passing position.

5. The system claimed in claim 2 wherein the adjustable control associated with the fluid acting on the valve comprises a cavity communicating with 'the fluid control valve, and a flow regulating device adapted to meter fluid flow into and out of the cavity;

6. The system claimed in claim 5 including a switch responsive valve disposed between the fluid control valve and the cavity forqcontrolling fluid flowingrelatively to the cavity, whereby shifting of the valve can be accurately controlled.

7. The system claimed in claim 2 wherein the self-closing line includes an adjustable fluid restriction for regulating the level of the initial breakaway driving force.

8. The system claimedin claim 2 wherein the line carrying fluid under. reduced pressure includes an adjustable fluid restriction. 1 v.

9. Thesystem claimed in claim 1 including means to move the fluid control valve in the self-closing line gradually to its closed position and progressively restricts the flow through the self-closing line to gradually reduce the driving force imparted to the door panel by the fluid operator.

10. The system claimed in claim 9 including means for gradually returning the fluid control valve from its closed to its open position after the demand signal disappears whereby another demand signal during the opening movement of the valve will cause the fluid operator to impart an initial driving force having a value correlated with the position of the valve between its closed and open positions. 

